As shown, extracted using binary contour cv2. MinAreaRect get minimum circumscribed rectangle of contour, but, because of some business, now need to separate the contours and the minimum circumscribed rectangle black areas, such as 1, 2, 3, 4, such as the maximum inscribed for the black area rectangle,

Now think of solution is: by reflecting changes in the minimum circumscribed rectangle area, and then cut out the area, and then to take the binary image, you can get 1, 2, 3, 4 regions, then use the corrosion can be clearly separated operation that several regions, then outline on these areas for operation,

Now I have a doubt, it is after the partition of the minimum circumscribed rectangle in dealing with how to return to the original?